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arXiv · 1212.6103

Pfaffian Systems of A-Hypergeometric Equations I: Bases of Twisted Cohomology Groups

Takayuki Hibi·Kenta Nishiyama·Nobuki Takayama
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Abstract

This is the third revision. We study bases of Pfaffian systems for $A$-hypergeometric system. Gröbner deformations give bases. These bases also give those for twisted cohomology groups. For hypergeometric system associated to a class of order polytopes, these bases have a combinatorial description. The size of the bases associated to a subclass of the order polytopes have the growth rate of the polynomial order. Bases associated to two chain posets and bouquets are studied.

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Takayuki Hibi, Kenta Nishiyama, Nobuki Takayama. 2014-06-17. Pfaffian Systems of A-Hypergeometric Equations I: Bases of Twisted Cohomology Groups. https://arxiv.org/abs/1212.6103

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